Yosemite National Park offers stunning views of mountain vistas during the day and star-filled skies at night. This view often includes the Milky Way -- invisible to almost one third of Earth’s population due to light pollution. Artificial lighting is restricted in Yosemite, but some areas in the park require lighting, such as parking lots and pathways between buildings. Light pollution can not only have a negative effect on visitors’ experiences, but can also change the natural rhythms of the park’s wildlife. University of California, Merced (UC Merced) graduate student Melissa Ricketts has found a solution – by turning one of her professor’s inventions upside down. In an article from UC Merced’s University News , Ricketts describes what she calls “prescribed irradiance distribution.” Ricketts is a member of UC Solar , a multicampus research institute headquartered at UC Merced headed by Roland Winston, the inventor of nonimaging optics. His compound parabolic concentrato...